High prevalence of dysfunctional sleep even in patients with spinal cord injuries and disorders who do not have sleep apnoea

4th May 2012

343

Sleep apnoea is thought to be the primary cause of sleep dysfunction in patients with spinal cord injuries and disorders, but a study published in Spinal Cord indicates that sleep dysfunction is also highly prevalent in patients with spinal cord injuries and disorders without sleep apnoea.

Sherri LaVela, research scientist, Center for Management of Complex Chronic Care, Hines VA Hospital, Hines, USA, and colleagues wrote that there is “abundant literature” on sleep apnoea in patients with spinal cord injuries and disorders, but there is limited literature for sleep dysfunction that is not related to sleep apnoea in these patients. Therefore, they surveyed patients with spinal cord injuries and disorders about their sleep function.

After excluding patients who had sleep apnoea, LaVela et al had data for 822 patients. The majority of patients had paraplegia (64%), the mean age of patients was 60 years, and the mean duration of injury was 20 years. LaVela et al found that 49% of patients had some form of sleep dysfunction, independent of sleep apnoea, which is considerably higher than the general population. They reported: “During the same time period as this study, the prevalence of dysfunctional sleep was 19% in the adult general population.”

Compared with patients who had normal sleep function, aside from being younger on average, the dysfunctional sleep group did not differ in demographic or injury characteristics in a bivariate analysis. However, a multivariable analysis showed that being white (p=0.04) was independently associated with sleep dysfunction. LaVela et al wrote: “This finding is in contrast to the general population findings of poorer sleep quality in non-white populations.” They also found that being a current smoker (p=0.0003), and alcohol misuse (p=0.03) were independently associated with sleep dysfunction.

Additionally, they identified certain health conditions that were associated with sleep dysfunction. LaVela et al wrote: “[The] odds of being a dysfunctional sleeper were higher in those with asthma (p=0.03), chronic obstructive pulmonary disease (p=0.05), and problematic weight gain (p<0.0001).”

In their conclusion, LaVela et al stated that this work “provides valuable information about sleep in veterans with spinal cord injuries and disorders”. They added: “Our findings indicate that sleep dysfunction occurs at a high prevalence in persons with spinal cord injuries and disorders, which warrants efforts and strategies to improve sleep outcomes.”

LaVela told Spinal News International: “There are a number of factors that may contribute to sleep dysfunction in individuals with spinal cord injuries. For instance, they may experience a reduced number of normal body shifts during sleep that can lead to discomfort and increased awakenings or they could be taking medications that disrupt circadian rhythm and the sleep-wake cycle. Other factors, such as limited daytime movement, depression, and pain may also contribute to dysfunctional sleep in some. Efforts to address the high prevalence of sleep dysfunction are sorely needed, especially since sustained sleep dysfunction may contribute to health deterioration and mortality in persons with spinal cord injuries. Our work suggests that efforts to improve sleep in persons with spinal cord injuries should include weight management, smoking cessation, and alcohol misuse prevention strategies.”